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ELECTRIC METER.

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Patented May 2', 1893.

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No. 496,728. Patented May 2 1893'.

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BLEGTRIG METER.

No. 496,728. Patented May 2, 1 893.

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No. 496,728. Patented May 2', 1893.

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(No Model.)

ELECTRIC- METER.

Patented May 2,1893.

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(No Model.)

J. EDMONDSON 8v-J; OULTON. ELECTRIC METER; No. 496,728. Patented May 2,1893.

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I UNITED STATES PATENT OFFICE.

JOSEPH EDMONDSON AND JOSEPH OULTON, OF BRADFORD, ENGLAND.

ELECTRIC METER.

SPECIFICATION forming part of Letters Patent No. 496,728, dated May 2,1893.

Application filed September 29, 1892. Serial No. 447,288. (No model.)

To aZZ whom it may concern.-

Be it known that we, JOSEPH EoMoNDsoN and JOSEPH OULTON, subjects of HerMajesty the Queen of Great Britain, residingatBradford, in the county ofYork, England, have invented certain new and useful Improvements inElectricity-ll/Ieters, of which the following is a specification.

This invention relates to improvements in electricity meters in whichthe vibrations of a chronometric balance or balances, pendulum orpendulums in combination with magnets or solenoids are made to recordthe amount of electric current or energy passing into consumption, andconsists in the use of a pendulum or pendulu ms each driven by an armactuated by gravity or by a spring such for instance as the gravity armsin the well known Becketts gravity escapement but lifted in our improvedmanner by electromagnetic force instead of by clockwork driven by aspring or weight.

In the case of a chronometric balance the impulse arm is actuated by aspring. It also consists in combining a resistance with a condenser andthe electric circuit of the electromagnet, so as to lessen or preventsparking at the point where the pendulum or balance opens, or closes thesaid circuit. It also deals with apparatus for stopping the saidpendulums or balances when the electric current is intermitted and alsofor restarting the said pendulums, or balances when the current is againswitched on such with electricity meters in which two pend ulums orchronometric balances are employed, such pendulums or balances beingrequired to'beat synchronously when no current is passing intoconsumption. In order the more effectually to insure such synchronism weattach the two pendulu ms to a bar which is common to both of them andwhich is itself held by a more or less elastic support. In the case oftwo chronometric balances we suspend these from more or less elasticsupports which are connected together by a rod or bar by which thevibrations are more or less communicated from the one to the other. Suchbeing the nature and object of our invention the following is a completedescription of same, in the case where two pendulums or chronometricbalances are used, reference being made to the accompanying drawings inwhich similar lettersof reference point to the same or similar partsthroughout.

Figure 1 is a front elevation of the pendulu m form of our improvedelectrical meter or apparatus for measuring and indicating the amount ofelectric current or energy passing into consumption such apparatus beingelectrically connected with a train of wheels and dials such asillustrated by Figs. 4, 5 and 6. Fig. 2 is a detail of part of Fig. 1drawn to an enlarged scale in order to show its construction moreclearly. Fig. 2 is is a similar View to Fig. 2 but showing the action ofthe magnet and weight reversed. Fig. 3 is'an end sectional elevation online A B of Fig. 1. Fig. 4 is a front elevation of the indicating dials.Fig. 5 is a plan view of Fig. 4 showing the train of wheels foroperating the hands of the dials. Fig. 6 is a detail of part of theindicating mechanism drawn detached in order to show its constructionmore clearly. Fig. 7 is a front elevation of a part of Fig. 1, drawndetached and with the pendulum rod removed in ordermorc clearly toillustrate part of the invention. Fig. Sis an end view of Fig. 7 thependulum rod bein in position. Fig. 9 is a plan view of Figs. 7 and 8showing the apparatus connected with a condenser. Fig. 10 is a similarview to Fig. 9 but showing a resistance coil connected to and combinedwith the apparatus and the condenser. Fig. 11 is a front elevation ofthe apparatus as constructed when chronometric balances are employed inlieu of the pendulums. Fig. 12 is an end view of a part of Fig. 11. Fig.13 is a plan view of part of Fig. 11 the position of the chronometricbalance being indicated bythe dotted lines. Fig. 13 is a detail of Fig.13 drawn to an enlarged scale in order to show its construction moreclearly. Fig. 14. is a similar view to Fig. 13, without the trappingmotion, which may be dispensed with in some cases.

Referring first to meters in which pendu lums are employed and to Figs.1, 2 and 3 of the accompanying drawings, at 11 are two pendulu mswhereof one is an ordinary pendulum which may be conveniently regulatedby a screw 33 as shown and the other is a pendulum influenced by thecurrent to be meas ured in any convenient manner. We prefer the methodshown in the drawings which 0011- sists of a fixed main coil 58 togetherwith the volt or high resistance coil and a correcting coil on thependulum as hereinafter described and marked 65. The pendulums are madeto vibrate the required motion being maintained by gravity impulse arms2-2 said arms 2-2 being mounted on axes free to move in the carryingframes or brackets 3-3 (see Figs. 7, 8, 9). Mounted loosely in the saidbrackets 3-3 and below each of the arms 2-2 is an armature 4 one end ofwhich is near to the electro magnet 5 and the other end is provided witha counterbalance weight 6.

On each pendulum rod 7 is a short cranked finger 8 (see Fig. 2) at theouter end of which is an adjusting screw 9 and, also a small bladespring 10 fixed at one end by a screw or otherwise on the said crankedfinger 8. The free end of the spring 10 rests on the adjusting screw 9.On the upper side of the spring 10 is a small projection, or a piece ofplatinum 11 which as the pendulum vibrates, comes into contact with asimilar projection 12 011 the impulse arm 2. A screw 13 (Figs. 7, 8 and9) limits the amount of movement of the armature 4. v

The action is as followsz-In a state of rest or in the normal positionthe counterbalance weight 6 holds the armature 4 in contact with thescrew 13 and away from the electro magnet 5 the gravity arm resting onthe top side of the armature 4. As the pendulum vibrates and moves tonearly the limit of its arc in in a reverse direction the gravityimpulse arm 2 falls with it until the arm rests upon the armature 4. Thecircuit is then opened by the part 11 moving awayfrom the part 12 andthe armature leaves, the magnet and lifts the gravity arm to itsoriginal position. It will be seen that the impulse arm falls through alonger are than that through which it is raised by the vibration of thependulum the difference being the height to which the impulse arm israised by the armature 4. The repeated fall of the impulse arm 2 throughthis short distance is sufficient to maintain the vibrations of thependulum. The impulse arm may be actuated by a spring instead of bygravity. It will be evident that the action of the magnet 5 and Weight 6may be reversed as shown in Fig. 2". In this case the impulse arm 2 ismounted in bushes which insulate it from the frame 3 its arbor beingelectrically connected to the bar 30 by a light flexible connection.When the impulse arm 2 rests on the top of the weight 6 the electriccircuit of the magnet 5' is completed the armature 4 is consequentlydrawn down and the impulse arm 2 is lifted along with the weight 6. Whenthe pendulum moves in the direction of the arrow and lifts the impulsearm 2 by means of the screw 9 the circuit is broken at 11-12, the magnet5 releases the armature 4 and the weight 6 falls as far as permitted bythe stop 13. When the pendulum moves in the reverse direction the arm 2falls with it until the arm rests again on the weight 6 completes thecircuit and the magnet 5 again lifts the weight 6 and arm 2 to the firstnamed position.

In order to lessen or prevent sparking at the points of contact 11-12whenever the electric circuit is opened or closed, we combine anordinary condenser such as 14 and a resistance coil such as 17 with theelectriccircuit of the electro magnet 5 a wire 15 from the frame 3 beingconnected with one side of the condenser, and a wire 16 connecting theopposite side of the condenser 14 and the resistance 17 (see Figs. 1 and10.)

The improved apparatus for stopping the pendulums 1-1 when the currentis intermitted, and for restarting the said pendulums when the currentis switched on, consists of an electro magnet 18 near the. bottom ofwhich is hinged an armature 19 the outer ends of which are cranked as at20 and the cranked ends 20-20 pass underneath the two arms 21-21 whichlatter rest on the cranked ends 2020. The arms 21-21 are at their innerends hinged, or free to move on fulcrum pins 22-22 and their outer endscarry the pins 23-23.. A hook 24 is fixed on the rod 7 of each of thependulums 1-1 in such a position as to engage with the pins 23-23 whenthese are in theirlowest position. When current is passing through thecircuit of the electro magnet 18 the said magnet holds up the armature19 which then supports the arms 21-21 in a position too high for thehooks 24-24 to engage with the pins 23-23. But when the current isswitched off the armature 19 falls and allows the arms 21-21 to fall bygravity to their lowest position. When this is so (as the pendulums 1-1vibrate toward one another) the inclined edges 25 of the hooks 24 willcomein contact with and move underneath the pins 23-23 until the latterfall into the catches 26-26 of such hooks. The pendulums 11 are thusstopped and will be held stationary at an elevation above their deadpoint. As soon as the electric current is again switched on,the electromagnet 18 will draw to it the armature 19 and the cranked ends 20-20will raise on their centers the arms 21-21 and pins mares the circuit ofthe magnet by way of the hooks 24-24 pins 2323 and arms21-21 ashereinafter described.

In order that the synchronism of the'two pendulums 1-1 may beefiectually maintained when no current is passing into consumption weattach the two pendulums 1-1 by the usual suspension springs 2727 to abar 28 common to both pendulums and this bar 28 is itself supported bysprings 2929 (or other elastic support or supports) which are attachedto a bar 30,secured to the box or casing of the meter. Passing through aslot or hole in the bar 28 is a screwed pin 31 fixed in the bar 30 andnuts 32 are placed on each side of the bar 28 so that the latter can beheld rigid or nearly so by causing the nuts 32 to nip it betweenthem.This bar 28 being thus made rigid or nearly so the pendulums 11 are madeto vibrate synchronously by the regulating weight 33 which is screwed upor down on the pendulum rod as required. The bar 28 is then releasedfrom the grip of the nuts 3232 and the synchronism is maintained by thevibration of the one pendulum being able to slightly influence those ofthe other. The screwed pin 31 and the nuts 32- 32 may be dispensed with,but in this case the primary adjustment of the pendulumsfor synchronismwill not be so accurate. When in lieu of the pendulums 11 we employchronometric balances 1-1 (see Figs. 11 and 13) the said balances 1 1being made to vibrate, their motion is maintained by the im-' pulse arms2-2 which are mounted on axes 35 free to move in the carrying frames or"brackets 33. On the axis 35 is a vibrating spring 34 (preferably similarto the balance spring of a watch). Mounted loosely in the brackets 3-3is an armature4 one end of which is near to the electro magnet5 but held(when no current is passing round such magnet) against the adjustingscrew 13 by the spring 6. It is shown in the drawings Fig. 13 asattracted by the magnet, and away from the said adjusting screw 13. 'Oneach balance 1 is a pin 11 which as the balance vibrates, comes incontact with the end 12 of the impulse arm 2.

The action is as follows: In a state of rest, or in the normal position,the spring 6 holds the armature 4 against the adjusting screw 13 andaway from the electro magnet 5. The impulse arm 2 then rests against thearmature'4 being retained there by the'force of the spring 34. As thebalance vibrates, and moves to nearly the limit of its arc in thedirection of the arrow the pin 11 will come in contact with the end 12of the impulse arm 2. The balance continues its motion through itssupplementary arc (the circuit being closed as hereinafter describedwhen referring to the coils and their connections)-the armature 4 isattracted to and held by the electro magnet 5. WVhen the balance movesin the reverse direction the impulse arm 2 is made by the spring 34 tofollow it until it comes in contact with the armature 4 the pin 11 thenleavesit behind, the'circuit is broken and the armature 4 being releasedthe spring 6 brings it back to the stop 13 and carries the impulse arm 2with it. It will be seen that the impulse arm 2 moves through ashorterare when carried by the balance in the direction of the arrow than whenit returns with it, the difference being the distance between theposition of the armature 4 when it is against the magnet and itsposition when against the adjusting screw 13. This difference gives therequired impulse to the balance.

The apparatus employed for stopping, and restarting the balances 1-1 issimilar to that described with reference to Figs. 1 and 3 excepting thatthe pin 23 is fixed to and at about the center of gyration of the radiusof the balance 1 and the springs 36 (see Fig. 13) are employed to keepthe arms 21-21 in contact with the cranked ends of the armature 19. Thearms 21-21 terminate in the hooks 24-24. As long as the current ispassing round the magnet 18 the armature is held by it and the arms21-21 are held with their books 24-24 out of reach of the pin 23 butwhenthe current is switched off the armature 19 is released and thehooks 24-24 are by'the springs 36 brought within range of the pins 23.which they catch and so hold the balances in a position away from theirneutral or dead point,

until the hooks are withdrawn by the renewed action of the current.

In order that the synchronism of the balances 1-1 may effectually bemaintained when no current is passinginto consumption we attach the twobalances 11 by the usual torsion suspension springs 2727 (Figs. 11 and12) which are supported by the much stronger springs 2929 or othersomewhat elasticsupport or supports attached to a bar 30 secured to thebox or casing of the meter. The elastic supports 29-29 are conn'ected'toone another by the bar 28 the supports 29 -29 being bent or having acrank formed on them, and these cranks 37 are received in the recesses38 formed one at each end of the bar 28 and held by means of the smallsprings 'of the recesses .3838.- The action, and -re-,

sult of suspending the balances 1; 1. as described is similar to thathereinbefore described in reference to' Figs. 1 and 3.

The index which records the amount of electric current or energy passinginto consumption to which we make no separateclaim consists of the dialsand hands (see Figs. 4 and 5) the hands being actuated by'the train ofwheels (see Fig. 5) such train of wheels be ing operated and operatingas follows. The electric circuits of the two electro-magnets 41-41 areconnected in series with the electric circuits of the magnets whicha'ctuate'the impulse arms (one to each) and near toeach magnet 41 is anaxis 42 (seen mostclearly in' Fig. 6) on which is fixed the armature 43and two cross arms -45 in which are pins 46-46 carrying the bladesprings 47-47 which engage with the teeth of a ratchet or catch wheel 48carried on an arbor 49 which passes through the slot 50 in the lever 44.On the arbor 49 is a pinion 51 gearing with and driving the wheel 52 ofthe differential motion 53 and on the arbor 49 is the pinion 51 gearingwith and driving the wheel 52 of the differential motion. When currentpasses around the electro magnets 41-41 (in consequence of the circuitsbeing closed at the contacts 11 and 12 by the vibration of the respective pendulums. or balances) the armatures 43-43 are attracted tosuch magnets 41-41 consequently the axes 42-42 are turned part of arevolution and the levers 44-44 are moved in the direction indicated bythe arrows in Fig. 6 the ends of the upper blade springs 47-47 come incontact with the teeth of the ratchet or catch wheels 48-48 and thelatter areturned a space of half a tooth. When the circuit is againopened the spiral springs 54-54 move the levers 44-44 in a reversedirection to that indicatedby the arrows in Fig. 6 and the lower bladesprings 47-47- now move the ratchet or catch wheels 48-48 a space ofhalf a tooth'in the same direction as before. This to and fro movementof the levers is repeated so often as the circuit is open and closed bythe pendulums or balances consequentlythe pinion 51 rotates and drivesthe wheel 52 in a reverse direction to that in which" the pinion 51drives the wheel 52'.- So long as thespeed of these wheels 52, 52 is thesame the wheel 55 will remain stationary. When the speed of the wheel 52varies from the speed of the wheel 52 in consequence of thedeviationfrom synchronism of the pendulums or balances caused by currentgoing into consumption the wheel 55 will rotate and set in motion thetrain of wheels or clockwork which drives the hands or indices. The stoppins 56-56 on the levers 44-44 prevent the ratchet or catch wheels 48-48moving more than the distance or space of half a tooth at one time orfor one vibration of the levers 44-44.

The electro magnets in this invention may beeither with or without ironcores and their armatures may be .either of iron or of a coil or coilsplaced in a shunt circuit and with or without iron cores.

Although we have here described the application of electrically actuatedimpulse arms on two pendulums 0r balances of electric m'eters where thebasis of measurement is the amount of variation from synchronism of the-the main wire for supplying the lamps.

+ main supply wire along which the current passes around the fixed maincoil 58 to the lamps. The wire 57 is connected by shunt wire 59 with thebar 30 through which a current for actuating the movements and indexpasses down the springs 29-29 and pendulum rods 7-7 and (when contact ismade between the parts 11-12) along the impulse arm 2 to the frame 3which is connected (as shown in Fig. 10) by the wire 15 to theresistance 17 thence by wire 15 to one side of the condenser 14 theopposite side of the condenser being connected by the wire 16 to the bar30 or the reverse as shownin Fig. 1. We

prefer inductive resistances as shown in the drawings and one of themmay be placed on each side of the condenser 14 if desired or thoughtnecessary. The circuit is continued from the frame 3 by wire 60 roundthe magnets 5-5 and by wire-61 to the index. Another current passesalong the pendulum-rod to the fork 63 thence by wire 64 to-correctingand volt coils 65 which are upon and form part of the pendulum orbalance and whose functions are hereinafter described. From thecorrecting coil 65 the current passes up the pendulum rod 7 by thewire66 away to A wire 67 from the volt coil 65 also passes along thependulum rod to the frame 3 of the electro magnet 18 and the currentflows by wire 68 to'said electro magnet and thence by wire 69 to thesupply terminal. The wires 66-67 may be carried inside the pendulum rod7 the latter being made hollow for this purpose. When the hooks 24-24are engaged with the pins 23-23 of the arms 21-21 a short circuit isformed between the pendulum rod 7 through such hooks 24 pins 23 arms 21and frame 3 to the electro magnet 18 thence to the supply terminal. Thevolt coil 65 being thus temporarily out out the magnet 18 is much morepowerful, and when the current is switched on the armature 19 isstrongly attracted and moves sharply to themagnet 18. The connectionsare similar when torsion balances are employed excepting that Wires70-70 are employed dipping into the mercury cups 71-71 by way of whichthe current passes as indicated in Fig. 11. It willbe seen that insteadof the current to the magnet 18 being passed through the volt coil, whenthe pendulums are vibrating it might equally well be passed insteadthereof through a separate coil of similar resistance coupled betweenthe frame 3 and the main wire 57, or further instead of the contactbetween the hooks 24 and the pins 23 cutting out the said separateresistance coil or the volt coil, the said contact might close thecircuit of a second coil placed on the core of the magnet 18 by whichthe magnetism would be temporarily increased as required. A very smallcurrent is continually passing through the shunt circuit which includesthe volt coil 65, the magnetic effect of which is in proportion to theelectro-motive force of the current. When current is passing throughthefixed main coil to the lamps, the magnetic force of the main coil and ofthe volt coil combined, accelerate or retard the vibrations of thependulum such acceleration or retardation being registered on the dialsand being, except as hereinafter described in proportion to the wattspassing into consumption. The force required to produce the vibrationsof a pendulum is in proportion to the square of the number ofvibrations. If therefore a equals the'normal numberof vibrations and 1)equals the number to be added by thecurrent the force required toproduce a will be a and to produce a-i-b will be a,+2ab+b the difference(2ab+b being the force to be exerted by the current under measurement.

With the volt coil alone the force actually ex-- erted would be in theratio Qab-l-b only. Upon each volt coil therefore there is wound thecorrecting coil carrying a very small proportion of the current passinginto consumption. If correctly calibrated this small current brings theratio up to Qab-I-b and makes the readings proportional throughout anyrange.

In the following claims we have used the term vibrating contact maker asbroadly defining the hereinbefore described pendulums and chronometricbalances, or their equivalents, and we wish to be so understood.

What we claim is 1. In an electric meter, the combination with avibrating contact maker of an impulse arm adapted to impel the saidcontact maker, an electro magnet, and an armature for the said magnetadapted to lift the said impulse arm, substantially as described.

2. In an electric meter, the combination with a magnet, of a vibratingcontact maker, an impulse arm lifted thereby through a part of itsmovement and making contact therewith, the said contact maker andimpulse arm being in circuit with the said magn'et,'and an armature forthe said magnet lifting the said impulse arm through the remainder ofits path, substantially as described.

3. In an electric meter, the combination with a vibrating contact makerhaving a hook thereon, of a coil mounted on the said contact maker, afixed electro magnet an electric circuit including the said magnet andhook, a second electric circuit including the said ma net and coil, anarmature for the said magnet, and a lever actuated by the said armatureand adapted to engage the said hooks, and to cut out the said coil andto short circuit the first named circuit through the said magnet,substantially as described.

4. In an electric meter, the combination with a plurality of vibratingcontact makers, of a flexibly suspended bar carrying the contact makers,whereby the vibrations of eachcontact maker slightly influences those'ofthe others, substantially as described.

5. In an electric meter, the combination with a magnet, of a vibratingcontact maker,

movement thereby and making contact therewith, the said contact makerand impulse arm being in circuit with the saidmagnet, an armature forthe said magnet adapted '[Ollffi the said impulse arm through th'ercinainder of its path and a condenser'placed' in a parallel circuit ofsuitable resistance to the said-magnet, contact maker, and impulse arii,substan- 'tially as described.

6. In an electric m'eter,'the combination with a vibrating contact makerhaving a hook thereon, of an impulse arm adapted to impel the saidcontact maker, an electro-magnet arranged in circuit with the saidcontact maker, and impulse arm, an armaturefor the said magnet adaptedto lift the said impulse arm, a second electro-magnet, and an armaturetherefor, and a lever actuated by the last named armature adapted toengage the hook upon the said contact maker, substantially as described.I

' 7. In an electric meter, the comb nation with a vibratin g contactmaker hav ng a hook thereon, of a coil carried on the sa d contactmaker, a fixed magnet, an electric circuit having includedtherein thesaid magnet and 0011, an armature for the said magnet, and a' leveractuated by the said armature and adapted to engage the hook upon thesaid contact maker, substantially as described.

8. In an electric meter, the combination With a vibrating contact maker,of an impulse arm adapted toimpel the said contact maker and to makecontact therewith, an electromagnet arranged in circuit with the saidcontact maker andimpulse arm, and an arma-' ture for the said magnetadapted to lift the said impulse arm, and to release it upon thecompletion of the circuit between the saidimpulse arm and the vibratingcontact maker, substantially as described.

I 9. In an electric meter, the combination with a vibrating contactmaker, of an impulse arm adapted to impel the said contact maker andmake contact therewith, an electro ma net in circuit with the saidcontact maker and impulse arm, and an armature therefor adapted to liftthe'said impulse arm, substantially as described. I

10. In an electric meter, the combination with a vibrating contact makerhaving a hook thereon, of a coil carried by the said contact maker, afixed electro-magnet, an electric circuit including the said hook, coiland electro magnet, an armature for the said magnet and a lever actuatedby the said armature and adapted to engage the said hook andelectrically connected with the said magnet, whereby the said coil willbe short circuited, substantially as described.

11. In an electric meter, the combination with a vibrating contact makerof an impulse an impulse arm lifted through a part of its by one of thesaid magnets and an armature for the other magnet adapted to raise thesaid impulse arm, substantially as described.

12. In an electric meter, the combination with a vibrating contact makerhaving a hook therein of an impulse arm adapted to impel and armature,and a lever actuated thereby and adapted when at rest to engage the hookupon the contact maker, substantially as described.

In testimony whereof wehave hereunto set our hands in the presence oftwo subscribing and make contact with the said vibrating conwitnesses.

tact maker, two magnets arranged in circuit JOSEPH EDMONDSON. with thesaid contact maker andimpulse arm, a I JOSEPH OULTON. clockwork drivenby one of the said magnets, WVitnesses:

an armature for'the other magnet adapted to WALTER BRIERLEY, lift thesaid impulse arm, an electro magnet J. BRIERLEY HOWARD.

